Modulating light incident on imaging sensor

Abstract

An image sensor, including: a sensing layer having a plurality of sensing elements, each sensing element configured to record impinging photons; and an attenuation layer coupled to the sensing layer, the attenuation layer configured with a plurality of attenuation elements to modulate light incident on the sensing layer. Key words include sensing layer and attenuation layer.

The invention claimed is: 
     
       1. An image sensor, comprising:
 a sensing layer having a plurality of sensing elements, each sensing element configured to record light incident on each sensing element; 
 an attenuation layer coupled to the sensing layer, the attenuation layer configured with a plurality of attenuation elements and placed between the light and the sensing layer, wherein each attenuation element is configured to modulate the light incident on each corresponding sensing element; and 
 a controller coupled to the attenuation layer and configured to individually control each of the plurality of attenuation elements and to adjust attenuation values of transparency of the plurality of attenuation elements, the controller configured to sequentially capture a plurality of images including first and second images from the sensing layer by (1) capturing the first image to determine which sensing elements are saturating, (2) changing the attenuation values for the plurality of attenuation elements corresponding to the saturating sensing elements by increasing the attenuation values by a pre-determined amount for only the plurality of attenuation elements corresponding to the sensing elements that are saturating, and (3) capturing at least one image subsequent to the first image. 
 
     
     
       2. The image sensor of  claim 1 , wherein the controller adjusts the attenuation values evenly over the sensing layer. 
     
     
       3. The image sensor of  claim 1 , wherein the controller is configured to combine the plurality of images to output a high-dynamic range image. 
     
     
       4. The image sensor of  claim 1 , wherein the controller is configured to apply a pattern of varying densities on the attenuation layer. 
     
     
       5. The image sensor of  claim 1 , wherein the attenuation layer is configured in multiple layers of independently-controlled attenuation. 
     
     
       6. The image sensor of  claim 1 , wherein the controller applies different attenuation patterns over time. 
     
     
       7. A method, comprising:
 recording light incident on a plurality of sensing elements of a sensing layer; 
 coupling an attenuation layer having a plurality of attenuation elements placed between the light and the sensing layer, wherein each of the plurality of the attenuation elements modulates the light incident on each corresponding sensing element of the plurality of sensing elements; 
 individually controlling each of the plurality of attenuation elements and adjusting attenuation values of transparency of the plurality of attenuation elements; 
 sequentially capturing a plurality of images including first and second images from the sensing layer by: 
 capturing the first image to determine which sensing elements are saturating; 
 changing the attenuation values for the plurality of attenuation elements corresponding to the saturating sensing elements by increasing the attenuation values by a pre-determined amount for only the plurality of attenuation elements corresponding to the sensing elements that are saturating; and 
 capturing at least one image subsequent to the first image. 
 
     
     
       8. The method of  claim 7 , wherein the attenuation values of the transparency are adjusted evenly over the plurality of attenuation element. 
     
     
       9. The method of  claim 7 , further comprising
 capturing a plurality of images sequentially at the attenuation values. 
 
     
     
       10. The method of  claim 9 , further comprising
 combining the plurality of images to produce at least one high-dynamic range image. 
 
     
     
       11. The method of  claim 7 , further comprising
 applying a pattern of varying densities on the attenuation layer. 
 
     
     
       12. The method of  claim 7 , further comprising
 applying different attenuation patterns over time. 
 
     
     
       13. An apparatus, comprising:
 means for sensing and recording light incident on a plurality of sensing elements; 
 means for attenuating the light incident on the means for sensing and recording placed between the light and the means for sensing and recording, the means for attenuating including a plurality of attenuation elements, wherein each attenuation element is configured to attenuate the light incident on each corresponding sensing element of the plurality of sensing elements; 
 means for individually controlling each of the plurality of attenuation elements configured to adjust attenuation values of transparency of the plurality of attenuation elements; 
 means for sequentially capturing a plurality of images including first and second images from the means for sensing comprising: 
 means for capturing the first image to determine which sensing elements are saturating; 
 means for changing the attenuation values for the plurality of attenuation elements corresponding to the saturating sensing elements by increasing the attenuation values by a pre-determined amount for only the plurality of attenuation elements corresponding to the sensing elements that are saturating; and 
 means for capturing at least one image subsequent to the first image.